The present invention relates to a staff for electronic level used for an electronic level.
As a conventional staff for electronic level, there has been known a staff for electronic level in which a barcode is formed on a surface of a rod-like elongated member whose cross section is a rectangle along a longitudinal direction at predetermined pitches in a predetermined pattern.
As the barcode, bars (black portions) extending in horizontal direction are engraved in the longitudinal direction at the predetermined pitches, widths (dimensions in up-and-down direction) of the bars change in a predetermined relationship. By detecting a change in width, it is possible to convert the pattern of the bars into a frequency, and further, by detecting a phase of the frequency, it is possible to measure a height.
Alternatively, as another barcode, bars having a plurality of types, e.g., seven types of different widths are engraved at equal pitches in a random pattern (so as to avoid the overlapping patterns), and by confirming the pattern, it is possible to measure a height.
In the staff for electronic level described above, in order to enable measuring a height at long range, a size of the pattern, a length of the staff for electronic level, and others are set. Therefore, the length of the staff for electronic level is as long as 3 m to 5 m, and the staff for electronic level is troublesome in terms of the carriage or the handling, e.g., a size or a weight.
Further, although there is an extensible staff for electronic level, it cannot be the that the convenience has been greatly improved in regard to a size, a weight, and others.
Furthermore, since a view angle of the electron level is not large, in the measurement at short range, only a part of the pattern of the barcode can be visually confirmed, and the workability of the measurement is deteriorated.